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241.
Larsson P Oyston PC Chain P Chu MC Duffield M Fuxelius HH Garcia E Hälltorp G Johansson D Isherwood KE Karp PD Larsson E Liu Y Michell S Prior J Prior R Malfatti S Sjöstedt A Svensson K Thompson N Vergez L Wagg JK Wren BW Lindler LE Andersson SG Forsman M Titball RW 《Nature genetics》2005,37(2):153-159
Francisella tularensis is one of the most infectious human pathogens known. In the past, both the former Soviet Union and the US had programs to develop weapons containing the bacterium. We report the complete genome sequence of a highly virulent isolate of F. tularensis (1,892,819 bp). The sequence uncovers previously uncharacterized genes encoding type IV pili, a surface polysaccharide and iron-acquisition systems. Several virulence-associated genes were located in a putative pathogenicity island, which was duplicated in the genome. More than 10% of the putative coding sequences contained insertion-deletion or substitution mutations and seemed to be deteriorating. The genome is rich in IS elements, including IS630 Tc-1 mariner family transposons, which are not expected in a prokaryote. We used a computational method for predicting metabolic pathways and found an unexpectedly high proportion of disrupted pathways, explaining the fastidious nutritional requirements of the bacterium. The loss of biosynthetic pathways indicates that F. tularensis is an obligate host-dependent bacterium in its natural life cycle. Our results have implications for our understanding of how highly virulent human pathogens evolve and will expedite strategies to combat them. 相似文献
242.
Tuzun E Sharp AJ Bailey JA Kaul R Morrison VA Pertz LM Haugen E Hayden H Albertson D Pinkel D Olson MV Eichler EE 《Nature genetics》2005,37(7):727-732
Inversions, deletions and insertions are important mediators of disease and disease susceptibility. We systematically compared the human genome reference sequence with a second genome (represented by fosmid paired-end sequences) to detect intermediate-sized structural variants >8 kb in length. We identified 297 sites of structural variation: 139 insertions, 102 deletions and 56 inversion breakpoints. Using combined literature, sequence and experimental analyses, we validated 112 of the structural variants, including several that are of biomedical relevance. These data provide a fine-scale structural variation map of the human genome and the requisite sequence precision for subsequent genetic studies of human disease. 相似文献
243.
Yen AS Gellert R Schröder C Morris RV Bell JF Knudson AT Clark BC Ming DW Crisp JA Arvidson RE Blaney D Brückner J Christensen PR DesMarais DJ de Souza PA Economou TE Ghosh A Hahn BC Herkenhoff KE Haskin LA Hurowitz JA Joliff BL Johnson JR Klingelhöfer G Madsen MB McLennan SM McSween HY Richter L Rieder R Rodionov D Soderblom L Squyres SW Tosca NJ Wang A Wyatt M Zipfel J 《Nature》2005,436(7047):49-54
The mineralogical and elemental compositions of the martian soil are indicators of chemical and physical weathering processes. Using data from the Mars Exploration Rovers, we show that bright dust deposits on opposite sides of the planet are part of a global unit and not dominated by the composition of local rocks. Dark soil deposits at both sites have similar basaltic mineralogies, and could reflect either a global component or the general similarity in the compositions of the rocks from which they were derived. Increased levels of bromine are consistent with mobilization of soluble salts by thin films of liquid water, but the presence of olivine in analysed soil samples indicates that the extent of aqueous alteration of soils has been limited. Nickel abundances are enhanced at the immediate surface and indicate that the upper few millimetres of soil could contain up to one per cent meteoritic material. 相似文献
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J H Abalain J Y Daniel H H Floch 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,290(12):795-798
A close correlation was evidenced between the length of a silastic capsule filled with testosterone propionate and the resulting plasma concentrations in testosterone in castrated male Quail. 5 days after the beginning of the treatment, testosterone induced in the spleen glands a conspicuous increase in total RNA, DNA and protein contents. 相似文献